1756-L71, 1756-RM2 and 1756-CNB firmware revision issue

Hello,

Is there any issue in term of the firmware revision for all of these three devices to communicate with each other in one rack?

I'm worried of L71 controller where it only support firmware revision 20 while 1756-CNB only support up till revision 16.057. I'm referring to the ControlLogix Standard Redundancy Firmware, Revision 16.057_kit1 Release Notes. Please help me on this matter because i'm a little bit confuse with the manual.

Thanks

You asked a similar question yesterday, with different modules.

The 1756-CNB modules are the problem; they cannot be used in an 'Enhanced Redundancy' system.

Because the 1756-RM2 only supports Enhanced Redundancy systems, it is not compatible with the 1756-CNB in a Redundancy Chassis.

If you are doing an upgrade, I strongly suggest using 1756-CN2(R)/B modules in the Redundancy Chassis. This will allow you to select the 1756-RM or 1756-RM2 that suits your needs, and also allows you to select Enhanced Redundancy, if that suits your needs.

The 1756-CNB modules can be employed as spare parts for the remote 1756 chassis in the system. ControlNet modules that are in 'remote chassis' rather than in the Redundant Controller chassis can be any type or version.

Thanks Ken for your explanation